Capstan



Patented Apr.- 2 2, 1930 UNITEDSTATES ALMON E. NORRIS, OF'BROOKLINE,MASSACHUSETTS 'cArSTAn 7' n li-cati 'n fi1edcMay 17, 192%.; serial No.191,998,

This invention relates to'capstans of the class in which the drivingmechanism for the head operates in an oil b'ath,.in a chamber which isclosed by the rotating head. Y

The invention will be best understood by reference to the followingdescription, when it taken inirconnection with the accompanying drawingof one illustrative embodiment thereof,- while its scope will be moreparticu-c 'larly pointed out in the appended claims.

In the drawing, the single figure shown is a central, vertical,sectional View of a capstan exemplifying the invention. 7

Referring to the drawing, and to theembodi'ment of the invention whichis selected I for exemplification, there is shown a capstan comprising acasing 4, presenting a base 5 surmounted by a head 6. The head ismounted to turn onupper and lower bearings 7 and 8, presented by'acolumn 9 upstanding from and herein conveniently formed as an integralpart of the base.

The base presents a wall 10, between which and the column 9 there is achamber 11, havingat its upper portionan annular opening 12. Thehead'thus presents a closure for this I opening,as it covers the entirespace between the walllO and the column 9. The chamber is protectedagainst the entrance of foreign matter by providing thehead with a skirt13, at

least as large in diameter as the opening 12,

'- and herein overlapping the latter. This skirt- 13 and the wall haveconfronting surfaces opposed end to end, and they-aresuitably'jconstructed to exclude foreign matter, and to preinner andouter depending flanges 14 and 15 on the skirt, presentingbetween theman'annular groove 16, which receives an upstanding V p 24-with'a'passage 29, affording communication between the upper portion ofthe chamber 11 and the'chamber 25, andby providing flange 17 presentedby the wall 10."

The depending flange 14 is provided with i" a-beveled surface 18, andthe upstanding flange 17 with a similar, but oppositely beveled surface19. The first bevel tends to prevent the oil in the chamber 11 fromcreep- I ing up into the jointpresented by the adj acent surfaces of theflanges 17 and lehwhile the second bevel forms an enlarged space orchamber, which tends to'break the adhesion of the oil, 'and to allow themaria gravitate backinto the casing. -When,'however, the

capstan is operated at high speed for along period of time,the heatgenerated by the driving mechanism within the chamber 11' is such as toexpand the air'therein. This tends to force oil'out between theinterjacent arts ofthe skirt 13 and the wall 10. Such lea age,

however, is entirely prevented b th means presently to be descrlbed. r

' Herein, the head prese ts twohubs 20and 21, turning on the upper andlower bearings v r 7 and 1 8 respectively. a The headhas an outer wall22, connected to the hubj20 by a wall 23, and to the lowerhub-21 by awall24. Between the wa11s231 and '24, there is a chamer25.'

The head isdriVen by suitable mechanism, 7

herein a worm gear 26,'conv.eniently secured I thereto asby cap screws27 extending into the wall 24:. This, gear is driven by a worm 28. Thisdriving mechanism is intended to run more, or lesslcompletely submergedin a bath of oil in the chamber-1'1. The gearin when run at'high speed,generates considerable heat, andfas. thereis little room in the chamberforexpansion of the air, when the latter, does expand to too great'anextent, oil

is likely, to be forced out of the 'chamberbea tweentheconfrontingsurfaces.of the base and the head. This'escapeiof oil isentirely'prevented providing -means for venting the.

air Space in the chamber 11 to the atmosphere,- 7 7 yet withoutin anywayrisking the-'possib'ils ity of water-or other foreign substancereachvent the "escape of .oil, as by providing them I with interj ac-entparts,'in the present example iof'oil' getting to the outside throughthe ventp a furtherpassage 30, afl'ording communication between the'chamber 25 and a-passage 31' provided-in the column The passage 31 inthepresent example is jin 'directfcom 'munication withtheatmosphere'through an opening 32 presented fby an annular plate 33,"whi'chis securedto the column by screws 34, and thus holds the head inplace on the column. The course taken by the air in travelling from thechamber 11 to the outer atmosphere is indicated by a series of arrows.

Having thus described one embodiment of the invention, but withoutlimiting myself thereto, what I claim and desire by Letters Patent tosecure is:

1. In a capstan, the combination of a base and a column, said basepresenting an outer wall and said column presenting an inner wall,between which walls there is a lower 7 chamber having at its upperportion an annular opening, said column presenting an opening leading tothe atmosphere, a head mounted to rotate about said-column, said headpresenting a closure for said annular opening, and a wall above saidclosure,there being an upper chamber between said closure and said wallthereabovasaid closure being provided with a passage afiordingcommunication between saidlower chamber and said upper witha passageaffording communication be- 5' tween said upper chamber and said openingleading to the atmosphere.

2; In a capstan, the combination of a rotatable head, means presentingav chamber, mechanism within said chamber for rotatso ing said head, andconduit means for venting said chamber to the atmosphere and preventingthe escape of lubricant therefrom.

3. In a capstan, the combination of arotatabl head,'a base and a columnproviding a support for said head and presenting a chamber having at itsupper portion an opening which is closed by said head, said head havinga hub, an outer wall, and .aweb connecting said hub and'outer wall, saidweb, be-

49 ing provided with anopening affording communication between saidchamber and, the space above said web, said column present.- ing aconduit leading from saidspace to the outer atmosphere, and mechanismwithin saidchamber for rotating said head.- a

- 4. In a capstan, the combination of a base presenting a chamber havingan opening at its upper portion, a column upstanding within said,chamber and extending upwardly therebeyond and presenting upper andlower h bearings, ahead closing said opening and have ing upper andlowerhubs about said upper and lower bearings, an outer wall, andlupper andlower websconnecting said hubs to said outer wall, said lower web havinga passage affording communication between said cham? her and the spacebetween said webs, said column having a passage which extends latorallyfrom said space and thence lengthwise 10 of. the axis of said column tothe outer atmos- V phere, and mechanism within said chamber for rotatingsaid head. r

In testimony whereof, I have signed my name to this specification.

a I ALMon-n. ulosBrsJ chamber, and said inner wall being provided a V V

